Drive system for armored electric vehicles

ABSTRACT

Embodiments of the invention relate to a drive system for armored electric vehicles and a method for its operation in event of a fire of the traction battery.

BACKGROUND Technical Field

Embodiments of the invention relate to a drive system for armored electric vehicles and a method for its operation in event of a fire of the traction battery.

Description of the Related Art

Electromobility will not stop, even for armored VIP vehicles for specially protected persons. With increasing range, electric vehicles in the near future can also be used on longer routes as a means of transportation for this group of persons. The development activities in this area are presently focusing on the mere protection of the passengers by strengthening the passenger compartment, as well as developing a weak responding battery system. However, both concepts quickly reach their limits in the extreme operational scenario of personal protection. In the event of an attack on or a striking of the vehicle and especially the HV battery, a “thermal runaway” of the HV battery can occur. There follows a chain reaction, resulting in a fire in all the single cells of the battery system with total loss of the vehicle. Furthermore, driving cannot continue due to safety shut-off circuits and structural damage to the cell assembly. An escape or continued driving of the person being protected is no longer assured in this case.

From DE 10 2004 026 237 A1 there is known a military wheeled vehicle with good mine protection, in which wheel axles and drive units are installed in the front and/or rear component and a residual mobility is assured by a preferably triple division of the vehicle body into front component, main component and rear component if the front component or the rear component is separated from the main component due to driving over a mine. A front component having at least one wheel axle and a rear component having at least one wheel axle are secured detachably at the front and rear to a main component by bolts having predetermined breaking points and/or explosive bolts which can be ignited by means of a built-in charge and exploded. In the front and/or rear component there is a combustion engine and/or an electrical drive motor, which then drives at least the one wheel axle in the front or in the rear component remaining on the main component after driving over the land mine.

US 2018/159 110 A1 discloses an electrical power supply system for use in an electric vehicle. The electrical power supply system comprises a tank, containing a plurality of batteries which are not secured to each other and which furnish electrical energy from the batteries to other systems of the vehicle. The tank comprises a release system, which can release some or all of the batteries from the tank or otherwise destroy them. Moreover, the system comprises a detector, which identifies an unwanted heating or thermal runaway of a battery within the plurality of batteries and causes the release system to release the batteries.

WO 2011/123 808 A2 relates to a battery system which monitors the status of a battery and assures safe conditions for a number of events affecting the safety of the battery cells, the battery pack or housing or a vehicle in which the battery is accommodated. In response to the safety event, the battery system provides one or more reactions in order to safeguard the battery, separate the battery, extinguish a fire, or maintain a safe temperature. Upon recognizing the safety event, the control system activates the safety device appropriately to assure safe conditions.

BRIEF SUMMARY

Some embodiments include a drive system for armored electric vehicles which prevents a burning of the entire vehicle even in event of a runaway or a fire in the traction battery and enables an escape or further driving of the person being protected.

DETAILED DESCRIPTION

Some embodiments include an armored motor vehicle with electric drive, comprising a high-voltage (“HV”) battery for the energy supply of the electric drive, being removably connected by explosive connection elements to the motor vehicle, and comprising a combustion engine which is adapted to start and assure the propulsion of the motor vehicle upon separation of the HV battery from the motor vehicle.

The HV battery for the energy supply of the electric drive (traction battery) of the armored motor vehicle described herein is removably connected by explosive connection elements to the motor vehicle. This allows for a total detachment of the HV battery from the overall vehicle in event of an attack on or a striking of the vehicle in which the HV battery is affected and responds with fire or explosion and smoke. Thus, the reaction of the HV battery is prevented from extending to the vehicle.

Pyrotechnic elements are used for the separating of the vehicle and the HV battery. In one embodiment of the armored motor vehicle, the HV battery is connected by explosive screws (similar to the door fastening in VIP armored vehicles) or explosive bolts to the motor vehicle.

A small combustion engine (internal combustion engine or ICE), such as a 1.4 l TFSI combustion engine, serves for taking over the propulsion after separation of the HV battery. Thus, the continuing propulsion and hence the possibility of escape are assured.

In one embodiment of the armored motor vehicle, the combustion engine is connected by a differential transmission in permanent and parallel manner to a drive train of the motor vehicle. In another embodiment, the combustion engine is connected to a drive train of the motor vehicle similar to a hybrid drive.

In another embodiment of the armored motor vehicle, the combustion engine generates electrical energy for the operation of the electric drive. The combustion engine works like a generator and generates enough power to continue operating the electrical drive with the aid of a power electronics. In one embodiment, the armored motor vehicle comprises an electrical independent wheel drive, i.e., each wheel is associated with a separate electrical machine. The combustion engine works like a generator and generates enough power to continue operating the electrical drive (electric motor) of at least one wheel with the aid of a power electronics. This assures the continued propulsion of the overall vehicle in event of a failure of individual wheels or electric motors.

In one embodiment of the armored motor vehicle, it is not recognizable from the outside that the motor vehicle has a combustion engine, in particular the exhaust gas system of the combustion engine is not visible from the outside. The installation of a combustion engine for emergency situations remains hidden from outsiders, in order to achieve a further safety enhancement, since an attacker will not be expecting a redundant drive system.

Some embodiments include a method for operating the armored motor vehicle described herein. In the method, upon overheating or fire of the HV battery the connection between the motor vehicle and the HV battery is exploded and the HV battery is entirely separated from the motor vehicle. Furthermore, the combustion engine is started and thus assures the further operation of the drive of the motor vehicle.

In one embodiment of the method, the combustion engine generates a torque which is coupled across a differential transmission into a drive train of the motor vehicle.

In another embodiment of the method, the combustion engine generates electrical energy to supply the electric drive of the motor vehicle. In another embodiment of the method, the motor vehicle comprises an electrical independent wheel drive and the combustion engine generates electrical energy to supply the electrical drive of at least one wheel of the motor vehicle.

Among the benefits of the embodiments described herein is the fact that BEV vehicles can be used for personal protection in public. Thus, even long distances can be covered with purely electrically operated vehicles. In event of an attack on or a striking of the vehicle, the danger zone of the HV battery and the extreme danger potential resulting from it are separated from the vehicle and the passenger compartment. Thanks to the use of an ICE, the vehicle however does not lose its propulsion ability, and thus the passengers are protected and have a chance to leave the danger area.

The features mentioned herein can be used not only in the particular indicated combination, but also in other combinations or standing alone.

German patent application no. 10 2022 103469.0, filed Feb. 15, 2022, to which this application claims priority, is hereby incorporated herein by reference, in its entirety.

Aspects of the various embodiments described above can be combined to provide further embodiments. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. 

1. An armored motor vehicle with electric drive, comprising: a high-voltage battery for the energy supply of the electric drive, being removably connected by explosive connection elements to the motor vehicle, and a combustion engine which is adapted to start and assure propulsion of the motor vehicle upon separation of the high-voltage battery from the motor vehicle.
 2. The armored motor vehicle according to claim 1, in which the electric drive is an electrical independent wheel drive.
 3. The armored motor vehicle according to claim 1, in which the combustion engine is connected by a differential transmission in permanent and parallel manner to a drive train of the motor vehicle.
 4. The armored motor vehicle according to claim 1, in which the combustion engine generates electrical energy for the operation of the electric drive.
 5. The armored motor vehicle according to claim 1, in which it is not recognizable from the outside that the motor vehicle has a combustion engine.
 6. The armored motor vehicle according to claim 5, in which the exhaust gas system of the combustion engine is not visible from the outside.
 7. The armored motor vehicle according to claim 1, in which the high-voltage battery is connected by explosive screws or explosive bolts to the motor vehicle.
 8. A method for operating an armored motor vehicle with electric drive including a high-voltage battery for the energy supply of the electric drive, being removably connected by explosive connection elements to the motor vehicle, and a combustion engine which is adapted to start and assure propulsion of the motor vehicle upon separation of the high-voltage battery from the motor vehicle, the method comprising: upon overheating or fire of the high-voltage battery, the connection between the motor vehicle and the high-voltage battery is exploded and the high-voltage battery is entirely separated from the motor vehicle and the combustion engine is started and assures further operation of the drive of the motor vehicle.
 9. The method according to claim 8, in which the combustion engine generates a torque which is coupled across a differential transmission into a drive train of the motor vehicle.
 10. The method according to claim 8, in which the combustion engine generates electrical energy to supply the electric drive of the motor vehicle. 